What is roof algae.
Streaks on roof.
The black streaks that you see on your roof didn t start off as streaks at all.
The black streaks are also known as black algae or roof mold.
The streaks look like mold but they re actually algae colonies that form in your shingles and feed on moisture and the limestone filler agents in the shingles.
Black stains on an asphalt roof caused by algae.
They re actually algae otherwise known as gloeoapsa magma and they are as nasty as they are resilient.
What are those ugly black streaks on my roof.
Technically the black streaks on roofs are a form of algae known as gloeocapsa magma.
If you re seeing black streaks running along your roof chances are you ve mistaken them for dirt or even mold.
Algae arrive on the rooftop through the air in the form of spores or clumps of cells.
Although these dark spots and ugly black streaks on your roof may look like dirt mildew soot or mold what they really are is algae.
Though often attributed to an accumulation of dirt defective shingles mold or mildew.
The algae feed off of the limestone within the roof shingles.
Believe it or not those black streaks only appear on roofs in certain areas of the country.
When rain hits the strips it produces a solution that runs down the roof and keeps algae moss and fungus from growing.
The black mold like stains and streaks that appear on roofs particularly light colored asphalt shingles is actually a blue green algae gloeocapsa magma.
Over time this algae accumulates developing a black outer coating which causes stains on roof shingles.
Black streaks on the north and west facing and shaded areas of your asphalt shingled roof can really wreck the appearance of your home.
Dark streaks or roof discoloration caused by algae happens in varying degrees across the u s especially in areas exposed to warm humid conditions.
It is most widespread in the eastern united states and is commonly found on roofs with northern exposure.
Most likely it started as a small circular patch a slight discoloration from the normal color of your shingles.
Commonly found in climates with warm humid summers it does no damage to the roofing but it certainly does looks bad.
The streaks are caused by a type of algae known as gloeocapsa magma.
If the streaks don t bother you or you re not ready to invest in a new roof install zinc or copper strips available at roofing centers along the top course of shingles.
If you live in a humid area of the country you ve probably seen unsightly dark streaks on asphalt shingle roofs.
Those that tend to be the most humid furthermore they will only appear on the north side of the roof.